Question: What is the greatest common factor of $3$ and $18$ ? Another way to say this is: $\operatorname{gcf}(3, 18) = {?}$
The greatest common factor is the largest number that is a factor of both $3$ and $18$ The factors of $3$ are $1$ and $3$ The factors of $18$ are $1$ $2$ $3$ $6$ $9$ , and $18$ Thus, the greatest common factor of $3$ and $18$ is $3$. $\operatorname{gcf}(3, 18) = 3$